The pericardium surrounds the heart like a protective sac. It contains fluid that decreases friction.
The lithosphere is the hard, brittle outer layer of the Earth, comprised of the crust and uppermost mantle.
ocean valleys...
Most of the middle layer in the heart wall is composed of cardiac muscle cells. Cardiac muscle cells are also known as cardiomyocytes.
The visceral pericardium.
You might be looking for the atria and ventricles, but these are just the chambers inside the heart. I have never heard of "heart pumps" before.
The outer layer of the sun is called the corona.
The muscle walls of the heart are called the myocardium. This thick, muscular layer is responsible for the heart's contraction and pumping action. It is located between the inner layer, the endocardium, and the outer layer, the epicardium, which together form the heart's structure. The myocardium varies in thickness depending on the heart chamber, being most prominent in the ventricles.
traphosphere
Cell membrane
The wall of the uterus is made up of three main layers. The inner most layer is the Endometrium. The middle layer is the Myometrium and the outer most layer is the Perimetrium, or adventitia or serosa.
Epidermis
i dont know ask ur mailman
The earth's solid rocky outer layer is called the crust. This is the thinnest layer of the Earth, which is divided into oceanic and continental crust. It is where all terrestrial life exists and where most geological processes take place.
corona is the outer most layer of the sun.
Since we have an atmosphere that is made up of 4 layers. One the most outer layer the thermosphere. Then the 3 most outer layer is the mesosphere. Next is the Stratosphere the third most outer layer. Last the closest layer the Troposphere which is where we all live.
The outermost layer of the Earth's Atmosphere is the thermosphere.
bark